jlg@lanl.ARPA (01/25/85)
> [...] But I notice that many > of the high end CD players (like my Revox) use the 14 bit > system. Are there advantages to the Phillips system that justify > the use of fewer bits? Do they use some kind of 'trick' to achieve > the same amount of resolution? I would appreciate a discussion of > the merits of these competing systems. Phillips uses the 14 bit system because 14 bit D/A converters are faster and more stable than 16 bit converters. This allows the Phillips system to send their samples to the converters at the 4xsampling rate that their digital filter uses. Phillips diddles the low order two bits of their 14 bit samples in order to produce an average value over 4 samples which matches exactly the value that a (properly digitally filtered) 16 bit sample at the normal sampling rate would have produced. So the resolution is not lost - Phillips has four times as many 14 bit samples per second as Sony has 16 bit samples. I have an article at home which fully describes the Phillips CD system. If there's an interest I will bring it in and post the source to the net. Others have mentioned this article before, so maybe someone else has the reference handy. ------------------------------------------------------------------------------ J. Giles